In general, a DC-DC converter may be used when a DC voltage greater or less than an input voltage is required.
The DC-DC converter generates a high spike voltage across each switching devices on a secondary side during switching.
To solve this, in recent years, a snubbed circuit is applied to the DC-DC converter to remove the high spike voltage.
A conventional DC-DC converter is disclosed in Korean patent application No. 2008-0039762.
The conventional DC-DC converter will be described. In the conventional DC-DC converter, a resistor R and a capacitor connected in series are connected to switching devices on a secondary side.
However, the conventional resistor and capacitor have a problem in that they are limited to removal of the spike voltage in a DC-D converter for large power.
Further, because the snubbed circuit has a resistor, heat is generated by the resistor to deteriorate device characteristics and to reduce the life duration.
Meanwhile, because only a coil and a rectifier are configured on the secondary side, the conventional DC-DC converter may not control a spike surge voltage generated when the rectifier is turned-off.
Furthermore, since coils wound in the secondary side are respectively wound around cores, there are problems in cost increase and size side.